If you search for examples of notable intelligence in the animal world, crows likely won’t catch your eye. But take another look.

For one thing, wild crows apparently can recall human faces, particularly when they’re associated with scary events. In one study, researchers wore various masks when interacting with crows. Some wore scary-looking masks when they trapped and banded crows, taking care not to harm any birds in an otherwise stressful process.

Still, when the researchers showed up later wearing the same scary masks, crows dive-bombed them and sent up alarm calls. Even crows uninvolved with the banding were stressed, presumably because they learned from their compatriots.

Crows also fashion twigs into hooked tools, which they use to pick bugs from wood. That tool-creating trait is another marker of advanced intelligence.